[Perf] Linux/arm64: 3 Improvements on 6/30/2026 11:06:07 PM +00:00

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [3ac60ce854ea8572cd8c510e838c7d4da85b21cb](https://github.com/dotnet/runtime/commit/3ac60ce854ea8572cd8c510e838c7d4da85b21cb)
Compare | [240be2ab0c0ee97dc4975eb9b3b7cc2908847793](https://github.com/dotnet/runtime/commit/240be2ab0c0ee97dc4975eb9b3b7cc2908847793)
Diff | [Diff](https://github.com/dotnet/runtime/compare/3ac60ce854ea8572cd8c510e838c7d4da85b21cb...240be2ab0c0ee97dc4975eb9b3b7cc2908847793)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Text.Json.Document.Tests.Perf_EnumerateObject

Benchmark | Baseline | Test | Test/Base | Test Quality | Edge Detector | Baseline IR | Compare IR | IR Ratio
-- | -- | -- | -- | -- | -- | -- | -- | --
|

• [EnumerateProperties - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 676.63 ns | 582.85 ns | 0.86 | 0.26 | False | | |

![graph]()
[Test Report]()

### Repro
General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

```cmd
git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Text.Json.Document.Tests.Perf_EnumerateObject*'
```

### System.Text.Json.Document.Tests.Perf_EnumerateObject.EnumerateProperties(TestCase: StringProperties)

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

[Profiling workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/profiling-workflow-dotnet-runtime.md)
[Benchmarking workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/benchmarking-workflow-dotnet-runtime.md)

---

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [3ac60ce854ea8572cd8c510e838c7d4da85b21cb](https://github.com/dotnet/runtime/commit/3ac60ce854ea8572cd8c510e838c7d4da85b21cb)
Compare | [240be2ab0c0ee97dc4975eb9b3b7cc2908847793](https://github.com/dotnet/runtime/commit/240be2ab0c0ee97dc4975eb9b3b7cc2908847793)
Diff | [Diff](https://github.com/dotnet/runtime/compare/3ac60ce854ea8572cd8c510e838c7d4da85b21cb...240be2ab0c0ee97dc4975eb9b3b7cc2908847793)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Buffers.Tests.ReadOnlySequenceTests<Byte>

Benchmark | Baseline | Test | Test/Base | Test Quality | Edge Detector | Baseline IR | Compare IR | IR Ratio
-- | -- | -- | -- | -- | -- | -- | -- | --
|

• [IterateGetPositionArray - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 23.01 ns | 20.35 ns | 0.88 | 0.24 | False | | |

![graph]()
[Test Report]()

### Repro
General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

```cmd
git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Buffers.Tests.ReadOnlySequenceTests*'
```

### System.Buffers.Tests.ReadOnlySequenceTests<Byte>.IterateGetPositionArray

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

[Profiling workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/profiling-workflow-dotnet-runtime.md)
[Benchmarking workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/benchmarking-workflow-dotnet-runtime.md)

---

### Run Information

Name | Value
-- | --
Architecture | arm64
OS | azurelinux 3.0
Queue | CobaltAzureLinux
Baseline | [3ac60ce854ea8572cd8c510e838c7d4da85b21cb](https://github.com/dotnet/runtime/commit/3ac60ce854ea8572cd8c510e838c7d4da85b21cb)
Compare | [240be2ab0c0ee97dc4975eb9b3b7cc2908847793](https://github.com/dotnet/runtime/commit/240be2ab0c0ee97dc4975eb9b3b7cc2908847793)
Diff | [Diff](https://github.com/dotnet/runtime/compare/3ac60ce854ea8572cd8c510e838c7d4da85b21cb...240be2ab0c0ee97dc4975eb9b3b7cc2908847793)
Configs | CompilationMode:tiered, RunKind:micro

### Improvements in System.Buffers.Tests.SearchValuesCharTests

Benchmark | Baseline | Test | Test/Base | Test Quality | Edge Detector | Baseline IR | Compare IR | IR Ratio
-- | -- | -- | -- | -- | -- | -- | -- | --
|

• [LastIndexOfAnyExcept - Duration of single invocation]()
• 📝 - [Benchmark Source]()
• [ADX - Test Multi Config Graph]()

| 176.78 ns | 149.41 ns | 0.85 | 0.20 | False | | |

![graph]()
[Test Report]()

### Repro
General Docs link: https://github.com/dotnet/performance/blob/main/docs/benchmarking-workflow-dotnet-runtime.md

```cmd
git clone https://github.com/dotnet/performance.git
py .\performance\scripts\benchmarks_ci.py -f net8.0 --filter 'System.Buffers.Tests.SearchValuesCharTests*'
```

### System.Buffers.Tests.SearchValuesCharTests.LastIndexOfAnyExcept(Values: "ßäöüÄÖÜ")

#### ETL Files

#### Histogram

#### JIT Disasms

### Docs

[Profiling workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/profiling-workflow-dotnet-runtime.md)
[Benchmarking workflow for dotnet/runtime repository](https://github.com/dotnet/performance/blob/master/docs/benchmarking-workflow-dotnet-runtime.md)

Start with the benchmark sources at src/benchmarks/micro/libraries/System.Text.Json/Document/EnumerateObject.cs, System.Buffers/ReadOnlySequenceTests.cs, and System.Buffers/SearchValuesCharTests.cs, then run the listed benchmarks with benchmarks_ci.py. Review the linked ARM64 reports and baseline/compare commits; done requires a clear triage decision for the reported improvements.

Written by the indexing model from the issue text.